plaid-mcp

Let an AI coding assistant (like Claude Code) answer questions about your own bank balances and transactions — by talking to the official Plaid CLI on your own computer.

This project doesn't store your bank data, doesn't see your bank credentials, and doesn't talk to Plaid's servers itself. It's a small translator program that sits between an AI assistant and a tool you already trust (the Plaid CLI), so the assistant can ask it questions like "what's my checking account balance?" or "list last month's transactions."

If you've never heard of "MCP" or "Claude Code" before, start with the next section — it explains everything from scratch. If you already know what those are and just want the tool reference, jump to Tool reference.

Contents

• New here? Start with this
• Is this safe? / Who should (and shouldn't) use this
• Glossary
• Prerequisites
• Setting up a Plaid account and the Plaid CLI
• Quick start
• Registering with Claude Code
• Using this with OpenCode
• Tool reference
• Error handling model
• Item health statuses
• Project structure
• Development
• Frequently asked questions
• Troubleshooting
• Non-goals / scope
• License

New here? Start with this

Three things you need to know about before any of this will make sense:

Plaid is a company that banks and financial apps use to securely connect to your bank account — it's the technology behind the "Connect your bank" button in apps like Venmo or budgeting apps. Plaid also publishes a command-line tool called the Plaid CLI that lets a developer log in to their own Plaid account and pull their own linked bank data from a terminal, without writing any code.

MCP (Model Context Protocol) is an open standard that lets an AI assistant call out to external programs — called "tools" — to do things it can't do on its own, like read a file, run a search, or (in this case) ask the Plaid CLI for your account balance. An "MCP server" is just a small program that offers a fixed set of these tools over a standard interface. This project is an MCP server: it offers six tools (listed below) that all revolve around reading Plaid data.

Claude Code is Anthropic's official command-line AI coding assistant. It can be extended with MCP servers, so that in addition to reading and writing code, it can also call out to tools like this one. This project was built for and tested against Claude Code, but since MCP is an open standard, any MCP-compatible client should be able to use it too — this README also includes setup steps for OpenCode, a popular open-source alternative (see Using this with OpenCode), and the same general approach should work for other MCP clients as well.

Put together: this repository is code you run on your own computer that lets Claude Code (or another MCP client) ask your already-set-up Plaid CLI for your own bank data, and hand the answer back to you in conversation — e.g. "What did I spend on groceries last week?"

Is this safe? / Who should (and shouldn't) use this

This project never sees your bank login, and never talks to Plaid's servers directly. All of that is handled entirely by the official Plaid CLI, which you install and log into yourself, independently of this project. This server's only job is to run CLI commands like plaid balance --json as a subprocess and hand back whatever the CLI prints out. There is no code anywhere in this repository that stores, transmits, or has access to a Plaid API key, access token, or bank password — which is also exactly why it's safe for this repository to be public: there's nothing secret in it to leak.

This is a good fit for you if:

• You're comfortable using a terminal / command line.
• You already use (or are willing to set up) the Plaid CLI with your own Plaid account and a real linked bank account.
• You use Claude Code (or another MCP-compatible AI assistant) and want it to be able to answer questions about your own finances.

This is not:

• A hosted service — there's no server to sign up for; you run it yourself, locally, and it only ever talks to your own machine's Plaid CLI.
• A way to view other people's bank data, or anyone's data but your own linked Plaid account(s).
• Officially affiliated with Plaid or Anthropic — it's an independent, personal project that happens to use both of their tools.

Glossary

Terms used throughout this README, in case any are unfamiliar:

Term	Meaning
Terminal / command line / shell	A text-based way of running programs on your computer, instead of clicking icons. On macOS this is the "Terminal" app; the commands in this README are typed there.
Repository ("repo")	A folder of code tracked by Git (see below), often hosted on a site like GitHub so others can view or download it.
Git / git clone	Git is the version-control tool that tracks changes to code. git clone <url> downloads a copy of a repository to your computer.
Node.js / npm	Node.js is a runtime for running JavaScript/TypeScript code outside a web browser; this project is written in TypeScript and runs on Node.js. npm is Node's package manager — npm install downloads the libraries this project depends on.
Plaid Item	Plaid's term for one linked bank connection (e.g. "my checking account at Bank X"). Referred to as item or item_id throughout this README and in the tools below.
MCP server	A program that exposes a set of "tools" an AI assistant can call. This project is one.
Tool	One specific action an MCP server offers — e.g. get_balances. Each tool has defined inputs and returns a defined kind of result.
stdio transport	The way this MCP server communicates with its client (like Claude Code): by reading/writing structured messages over standard input/output, the same input/output channel a terminal program normally uses for text. You don't need to understand the mechanics of this — it just means "runs locally as a subprocess," not "listens on the network."
--json flag	A flag supported by the Plaid CLI that makes it print machine-readable JSON output instead of human-formatted text. This server always uses it.

Prerequisites

You'll need all of the following installed and working before setting up this project. None of them are things this project installs for you.

Requirement	What it is	How to get it
A terminal	See glossary	Built into macOS/Linux ("Terminal"); on Windows, use WSL or Git Bash.
Git	Used to download this repository	brew install git (macOS) or see git-scm.com/downloads
Node.js v22 or newer	Runs this project's code	Download from nodejs.org (includes npm), or brew install node on macOS
Plaid CLI (plaid)	The tool this server talks to	See Setting up a Plaid account and the Plaid CLI, below
A Plaid account, logged in via the CLI	Lets the CLI actually fetch your data	See Setting up a Plaid account and the Plaid CLI, below
At least one linked bank ("Item")	The actual bank connection you want to ask about	See Setting up a Plaid account and the Plaid CLI, below
Claude Code	The AI assistant that will use this server	See Anthropic's installation instructions

Check your Plaid CLI setup works before going any further — every tool in this project will fail the same way if this part isn't working yet:

plaid config           # shows whether you're logged in
plaid item list --json # should print your linked bank(s) as JSON, not an error

If either of those doesn't work, fix that first (usually by running plaid login and/or plaid link, both covered step by step below) — this project can't do anything the CLI itself can't already do.

Setting up a Plaid account and the Plaid CLI

If you've never used Plaid before, this section walks through everything from "I have no Plaid account" to "the CLI can see my real bank balance" — all of it happens through Plaid's own CLI and dashboard, before you ever touch this project's code.

1. Install the Plaid CLI

The official Plaid CLI docs only document one installation method, via Homebrew:

brew install plaid/plaid-cli/plaid

• macOS: works directly, as above. If you don't have Homebrew yet, install it first from brew.sh.
• Linux: Homebrew also works on Linux (Linuxbrew) — install Homebrew first, then run the same command.
• Windows: Plaid doesn't document a native Windows install. The most reliable path is to install WSL (Windows Subsystem for Linux), then install Homebrew and the CLI inside your WSL Linux environment as above.

Confirm it installed correctly:

plaid --version

2. Create a Plaid account

If you don't already have one, sign up right from the CLI:

plaid register

This opens Plaid's dashboard signup page in your browser. Create your account there (email/password or SSO, plus verifying your email) — this is Plaid's own signup flow, not anything specific to this project.

Every new Plaid account automatically gets access to the Sandbox environment — a fake/test environment with fake banks and fake data, meant for developers to try things out safely. Sandbox alone isn't enough to see your own real bank data — for that, you need Production access, which is the next step.

3. Log in via the CLI

plaid login

This opens your browser to log in to the account you just created. Once you approve it, the CLI stores your login locally and automatically fetches your API keys — you don't need to find or copy/paste any keys yourself.

4. Get approved for Production access (to use a real bank)

By default your account can only use Plaid's fake Sandbox data. To connect an actual bank account, you need to apply for Plaid's Trial plan:

plaid trial

This opens a short application form in your browser — no business paperwork required for the Trial plan, and Plaid states that around 90% of applicants are auto-approved within about 60 seconds. Once approved, pull down your newly-unlocked Production API keys:

plaid keys fetch

5. Link a real bank account

plaid link

This opens Plaid's own "Link" flow in your browser — the same secure bank-connection widget used by apps like Venmo. Search for your bank, log in with your real online banking credentials (this happens inside Plaid's own widget — this project, and the Plaid CLI itself, never see or store your bank password), and choose which account(s) to connect. Plaid calls each connection you create this way an Item (see Glossary).

6. Confirm it worked

plaid item list --json

This should print JSON describing the bank connection you just linked. If it does, you're fully set up — continue to Quick start to set up this project itself.

Quick start

Once every item in Prerequisites above is working, here's the whole setup, start to finish:

# 1. Download this project
git clone https://github.com/nicholasg-dev/plaid-cli-mcp-server.git
cd plaid-cli-mcp-server

# 2. Install its dependencies
npm install

# 3. Compile it (this project is written in TypeScript, which needs to be
#    turned into plain JavaScript before it can run)
npm run build

# 4. Tell Claude Code about it
claude mcp add plaid --scope user -- node $(pwd)/dist/index.js

That's it. Open (or restart) Claude Code and ask it something like "What's my current bank balance?" — it should recognize it has a plaid tool available and use it.

To confirm it's registered correctly at any point:

claude mcp list        # "plaid" should show up as connected

Registering with Claude Code

The one command from step 4 above, explained:

claude mcp add plaid --scope user -- node $(pwd)/dist/index.js

This tells Claude Code: "there's an MCP server named plaid; to start it, run node on this compiled file." Everything after -- is the exact command Claude Code will run as a subprocess whenever it needs to use one of this server's tools.

--scope user matters: it registers the server for every Claude Code session on your computer, not just when you happen to be working inside this specific folder (which is what claude mcp add does by default, without --scope user). Since asking about your bank balance isn't tied to any one coding project, user scope is almost always what you want here.

Useful follow-up commands:

claude mcp list          # see all registered MCP servers, and whether they're connected
claude mcp get plaid     # see the exact command Claude Code has stored for "plaid"
claude mcp remove plaid  # unregister it

If you later move this folder to a different location on disk, re-run the claude mcp add command from that new location — the registration stores an absolute file path, which won't update itself.

Using this with OpenCode

OpenCode is another open-source, terminal-based AI coding assistant, unrelated to Anthropic, that also supports MCP servers. This project works with it the same way it works with Claude Code — same prerequisites, same compiled dist/index.js — only the registration step is different, since OpenCode is configured via a JSON file instead of a CLI command.

1. Build this project first, if you haven't already (see Quick start):

npm install
npm run build

2. Add it to an OpenCode config file. OpenCode reads a JSON config file either per-project (opencode.json in your project's root folder) or globally, for every project (~/.config/opencode/opencode.json — create this file and any missing folders in the path if it doesn't exist yet). Global is usually what you want here, for the same reason --scope user is recommended for Claude Code above: your bank balance isn't tied to any one coding project.

Add a "plaid" entry under "mcp", using the absolute path to this project's compiled dist/index.js:

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "plaid": {
      "type": "local",
      "command": ["node", "/absolute/path/to/plaid-cli-mcp-server/dist/index.js"],
      "enabled": true
    }
  }
}

Replace /absolute/path/to/plaid-cli-mcp-server with wherever you cloned this repository — run pwd inside the project folder to get that path. If a "mcp" key (or the file itself) already exists with other servers in it, just add the "plaid" entry alongside them rather than replacing the whole file.

3. Confirm it's picked up:

opencode mcp list   # "plaid" should appear, enabled

Then, from an OpenCode session, ask it something like "what's my bank balance?" the same way you would with Claude Code — it should recognize and call the plaid tools automatically.

Tool reference

This section is the detailed reference for each of the six tools this server offers. You won't normally need to read this to use the server — just ask Claude Code what you want in plain English and it'll pick the right tool. This section is for understanding exactly what's happening under the hood, or for developers extending this project.

All inputs are validated with zod schemas that map 1:1 onto the underlying plaid CLI's own flags — nothing is renamed or reshaped between what the AI assistant sends and what the CLI receives. Every tool call runs plaid <subcommand> ... --json and returns the parsed JSON as the result.

A successful tool call looks like:

{
  "content": [{ "type": "text", "text": "<pretty-printed JSON from the CLI>" }]
}

A failed one sets isError: true, with the Plaid CLI's own error message as the content (see Error handling model):

{
  "content": [{ "type": "text", "text": "<error message from the plaid CLI>" }],
  "isError": true
}

---

list_items

Lists every bank connection ("Item") you've linked via the Plaid CLI.

• Runs: plaid item list --json
• Inputs: none
• Returns: an object with an items array; each entry has at least an item_id, which you can pass to the other tools below.

This is usually the first tool called, since every other tool that takes an item argument needs an item_id from here.

get_item

Gets details for one linked Item, including its accounts.

• Runs: plaid item get --item <id> --json

• Inputs:

  Field	Type	Required	Description
  item	string	yes	The item_id to look up (from list_items)

• If the item id doesn't exist: returns isError: true with a message containing ITEM_NOT_FOUND (see Item health statuses).

get_balances

Gets current account balances — for one linked Item, or all of them.

• Runs: plaid balance --json [--item <id> | --all]

• Inputs:

  Field	Type	Required	Description
  item	string	no	Only get balances for this one Item
  all	boolean	no	Get balances for every linked Item

  Only specify one of item or all, not both — that mirrors the Plaid CLI's own rule, which this server doesn't duplicate; it just passes along whatever you asked for and lets the CLI validate it.

list_transactions

Lists transactions in a date range.

• Runs: plaid transactions list --json [--item <id> | --all] [--start-date <date>] [--end-date <date>] [--count <n>] [--offset <n>]

• Inputs:

  Field	Type	Required	Description
  item	string	no	Only this one Item
  all	boolean	no	Every linked Item
  startDate	string (YYYY-MM-DD)	no	Start of the date range. If left out, the CLI defaults to the last 30 days.
  endDate	string (YYYY-MM-DD)	no	End of the date range
  count	integer	no	Maximum number of results to return
  offset	integer	no	How many results to skip (for paging through a long list)

sync_transactions

Fetches only new or changed transactions since the last time this was called, using Plaid's official incremental-sync mechanism. Useful for "what's changed since I last checked."

• Runs: plaid transactions sync --json [--item <id> | --all] [--limit <n>] [--page-size <n>]

• Inputs:

  Field	Type	Required	Description
  item	string	no	Only this one Item
  all	boolean	no	Every linked Item
  limit	integer	no	Maximum total results to return
  pageSize	integer	no	How many results to fetch per underlying request

  The first time this runs for a given Item, it returns that Item's full transaction history (there's nothing to compare against yet). Every call after that only returns what's new or changed. The bookkeeping needed to know "what's changed since last time" (called a cursor) is handled entirely by the Plaid CLI — this project doesn't store or manage it.

check_item_health

Checks whether one or all linked Items are working normally, or need your attention (e.g. because a bank requires you to log in again).

• Inputs:

  Field	Type	Required	Description
  item	string	no	Check just this one Item. Left out: checks every linked Item.

• How it works: the Plaid CLI has no single "check health" command, so this tool does it in two steps: list the Item(s) to check (via plaid item list, unless you gave a specific item), then run plaid item get on each one and see whether it succeeds. If checking multiple Items, one broken Item won't stop the others from being checked — you always get a result for every Item you asked about.

• Example result:

  [
    { "itemId": "abc123", "status": "healthy" },
    { "itemId": "def456", "status": "re_auth_required" }
  ]
  

  See Item health statuses for what each possible status value means.

Error handling model

Every call to the Plaid CLI goes through one function (src/plaidCli.ts) — nothing else in this codebase runs the plaid binary directly. It always runs the CLI safely (as a plain argument list, never as a shell command string someone could tamper with), and always adds the --json flag.

• If the CLI exits successfully: its JSON output is parsed and returned as the tool's result.
• If the CLI exits with an error: whatever it printed as its error message is captured, and the tool returns a normal (non-crashing) result with isError: true and that message as the content. This covers things like: not being logged in, an unrecognized item id, a malformed date, or the plaid program not being found at all.

For example, asking about an Item that doesn't exist produces an error message shaped like this from the CLI itself:

{"error":{"code":"ITEM_NOT_FOUND","message":"no item matching \"bogus-item\" found","type":"INVALID_INPUT"}}

Item health statuses

check_item_health reads the Plaid CLI's error messages and turns them into one of these plain-English statuses:

Underlying Plaid error code	status returned	What it means
(no error — the check succeeded)	healthy	Everything's working normally
ITEM_LOGIN_REQUIRED	re_auth_required	The bank needs you to log back in via plaid link (common after a password change on the bank's side)
ITEM_LOCKED	item_locked	The bank connection is temporarily locked
PENDING_EXPIRATION	pending_expiration	The connection will need re-authentication soon
ITEM_NOT_FOUND	not_found	That item_id doesn't exist
anything else / an unrecognized error	unknown_error	See the reason field in the result for details

Project structure

For anyone looking to read or modify the code:

plaid-mcp/
  src/
    index.ts         # Starts the MCP server and registers all six tools
    tools.ts          # Defines each tool's inputs and what it does when called
    plaidCli.ts        # The one place that actually runs the `plaid` CLI program
    itemHealth.ts      # Logic behind check_item_health
  tests/               # Automated tests (see Development, below)
  dist/                # Compiled output — created by `npm run build`, not checked into Git
  package.json         # Project metadata and dependency list
  tsconfig.json         # TypeScript compiler settings

Development

npm test    # runs the automated test suite
npm run build
npm start   # runs the compiled server directly, for manual testing

Note: the test suite runs against your real, logged-in Plaid CLI — there are no fake/mock responses. That means running npm test requires the same setup as using the server day-to-day (see Prerequisites): plaid installed, logged in, with at least one bank linked.

Frequently asked questions

Does this project ever see my bank password or Plaid API keys? No. It only ever runs commands like plaid balance --json and reads the output. All login and credentials live inside the Plaid CLI's own local configuration, which this project never reads or touches.

Is my data sent anywhere other than my own computer and Plaid? This project itself makes no network calls at all — it only starts a local subprocess (plaid) and reads its output. Whatever Claude Code (or whichever AI assistant you're using) does with the resulting data — e.g. sending it to Anthropic's API as part of your conversation — is between you and that assistant, the same as with anything else you ask it about.

Is this an official Plaid or Anthropic product? No — this is an independent personal project. "Plaid" and "Claude Code" are the names of the respective companies' own products that this project integrates with; this repository isn't published or endorsed by either company.

Can I use this with something other than Claude Code? Yes — see Using this with OpenCode for a second, fully-documented client. More generally, since MCP is an open standard, any MCP client that supports stdio-transport servers should be able to run it the same way; consult that client's own documentation for how to add an MCP server by command or config file.

Can this create new bank connections, or move money? No. It only reads data that's already there (linked Items, balances, transactions). There's no code path anywhere in this project that links a new bank, removes one, or initiates any transfer or payment. See Non-goals / scope.

Troubleshooting

Symptom	Likely cause / fix
command not found: plaid (or every tool call errors similarly)	The plaid CLI isn't installed, or isn't on your PATH. Run which plaid in the same terminal Claude Code uses to confirm it can be found.
command not found: node or npm	Node.js isn't installed — see Prerequisites.
Tool calls fail with a login/auth-related error	Run plaid login again — your CLI session may have expired.
One specific bank ("Item") keeps failing	Run the check_item_health tool (or plaid item get --item <id> --json directly) to see exactly why — often it just needs plaid link run again for that bank.
claude mcp list doesn't show plaid, or shows it as disconnected	Re-run the claude mcp add command from Quick start. Make sure npm run build has been run so dist/index.js actually exists.
Made a code change but nothing seems different	Run npm run build again — Claude Code runs the compiled dist/ files, not the TypeScript source directly.

Non-goals / scope

To be explicit about what this project intentionally does not do:

• No write access. It can't link a new bank, remove one, or move money — only ever reads data from banks you've already linked yourself.
• No direct connection to Plaid's servers. All communication with Plaid goes through the official CLI; this project never calls Plaid's API directly.
• No investments or liabilities data — only Items, balances, and transactions are covered.
• No credential storage. Login and API keys are entirely the Plaid CLI's responsibility; this project has nowhere to keep them even if it wanted to.

License

MIT — free and open source. You're welcome to use, modify, and distribute this code, including commercially, as long as the original copyright notice is kept. See the LICENSE file for the full text.